People like Fred Thompson. So far as I can tell, that is currently the prime rationale for his candidacy for president of the United States. He doesn’t need to launch a media blitz to achieve this level of public fondness. His avuncular, crumpled tower of a personage is well known from many episodes of Law & Order.

In this year’s race, only one other Republican candidate has even minimal charm – the obscure Mike Hucka-bee of Arkansas, who is obviously (and rather successfully) running for vice-president. Rudy Giuliani is many things, but likable isn’t one of them. Mitt Romney has failed to win over many conservatives despite an impeccable family life and a platform largely dictated by the far-right activist base. The slickness and eagerness to please seem to glide past any political traction. John McCain is too prickly to be cuddled. But good old Fred has the shtick down.

Last Wednesday he lolloped onto The Tonight Show with Jay Leno, skipping the Fox News Republican debate in New Hampshire, and announced for president. It was an unconventional entrance, disdained by even conservative talk show host Rush Limbaugh for its celebrity-driven aura. But it worked well enough.

The way Thompson drawls backwards into an answer, the manner in which he almost fails to finish his sentences because of boredom or his easy-going way, the gentle, inclusive humour, the effortless stage presence of an actor/lawyer: all these came across beguilingly. I’ll admit it: I like him. He’s been charming when we’ve met; and once you get over craning your neck upwards to see his lofty face, you find yourself wanting him to do well.

Of course, you’re not too sure what exactly he would do. Iraq? It’s the biggest question in the election, and I have absolutely no idea what Thompson favours. He says he wants the country to show resolve and fortitude. He was for the war. What now? “We stay until we get the job done.” Which means: “Until it is pacified enough that the people of Iraq have a free life and don’t get killed by Al-Qaeda . . . We cannot afford to go into a situation and not show resolve.”

Do we therefore withdraw now from Baghdad? Or Anbar? Do we add troops? Do we remove them? How quickly? These questions – vital ones, being debated not at some future date, but now – remain opaque in Thompson’s worldview.

He’s hostile to Iran’s regime, but has not offered any explicit strategy to deal with it. He’s George W Bush with a Valium and a more reassuring demeanour. That may be enough for the Republicans; but it is surely insufficient for the global hyper-power in a historic crisis of foreign policy.

Thompson is accused of being lazy. So was Ronald Reagan, of course. But there is a key difference between the Reagan of 1979 and the Thompson of 2007. Reagan had spent a lifetime honing arguments, finessing policy, articulating a broad philosophical view, while proposing concrete and radical policy options.

Thompson has a legislative record as a senator from Tennessee that is all but invisible. Yes, he has a solid conservative record on taxes and other people’s spending. But he was a hog for his home-state pork barrel projects. He was, in other words, a popular backbencher – but no more. At times his candidacy feels merely like a rationale for a man who senses that Americans are deeply uneasy about their current leadership, wants to reassure them, but has no idea substantively how.

A thinker he isn’t. He’s rather a conveyor of mood. In a period of less moment, when less is at stake, this might be an aesthetic preference: a calm presence in a storm. But on the substance of war, and foreign policy, the Thompson shtick can seem somewhat detached from the needs of the moment.

But he squares a Republican circle. Thompson is a Southern social conservative with mass appeal. He’s not a fire-breather, and not a Bible-thumper. No one can imagine him dragging women into jail for abortions. On marriage, he favours a federal constitutional amendment – but only to ensure that no state is forced to adopt same-sex marriage because of another one.

He also manages to frame his candidacy as somehow untainted by recent Republican incompetence and harshness. At times he almost sounds like Barack Obama, the Democratic contender, arguing that “problems will be dealt with when our leaders come together, as adults, and honestly seek solutions that extend past the next election cycle”. Unlike Obama, however, Thompson has almost no solid agenda to run on.

His fundraising has also been underwhelming, with a mere $3m in the second quarter (a fraction compared with Romney, Hillary Clinton or Obama). His formal announcement on September 6, moreover, means he won’t be required to file a third quarter fundraising total – suggesting a desire to keep embarrassingly low numbers out of the public eye.

His campaign has also been staggering from defections even before it began – and his wife Jeri has raised hackles among campaign staffers for her controlling tendencies. She is, it bears noting, a full 24 years younger than her spouse – and Thompson’s 17-year history of bachelor life before his 2002 marriage, may yet give him grief on the campaign trail among evangelicals.

The populist aura may also fade. His “aw shucks” regular guy routine wears thin once you see all the lucrative lobbying he has done since leaving the Senate. Yes, he once famously toured Tennessee in a red pickup truck. But he often had someone else drive and followed behind in a silver luxury sedan. If he is a Tennesseean, he is one with a dollop of Hollywood and Washington on top.

He has entered the race late but is second in the national polls for the Republican candidacy. Take that with a grain of salt. At this point, any halfway credible Republican not tainted with the Bush brush and with high recognition would be high up in the current field. But Thompson’s regional strength is real – and largely in the South.

With the major Republican candidates hailing from New York, Massachusetts and Arizona, that matters. The Republicans are a Southern party now. The candidate designed to appeal to them – Northeastern/Mid-western Mormon, Mitt Romney – just hasn’t caught on. It is hard to believe his Mormonism has nothing to do with this.

And so Thompson emerges in the widening sectarian and political gap. Buoyed by celebrity, unencumbered by actual policies, platitudinous on Iraq, but oozing calm, he is the antianxiety medication for a troubled America. I’m just not sure a sedative is what the country really needs right now. A wake-up call would be more appropriate.

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